2D barcodes are data carrier used to assign a unique or batch identity to a product, document or any other item. Such 2D barcodes are preferably formed by a two-dimensional grid defining a 2D matrix whose cells are coded with information, notably binary information such as 0 or 1 coding bits which in series can code different type of characters.
According to the invention all two-dimensional bar codes (2D bar codes) are concerned, and notably the very common following ones: PDF-417, MaxiCode, Datamatrix, QR Code, Aztec Code, and EAN barcodes. These barcodes can be read up to a certain degree of damage, using for instance Reed-Solomon error correction to allow correct reading even if a portion of the bar code is damaged. When the bar code scanner cannot recognize a bar code symbol, it will treat it as an erasure. Now, QR Code (Quick Response Code) and Datamatrix are the 2D bar codes used in more and more applications in diverse industries as manufacturing, warehousing and logistics, retailing, healthcare, life sciences, transportation and office automation. These are also the 2D barcodes most used by consumers to access digital information related to a physical medium.
The QR Code being the most frequently used type to scan with smartphones, with the explosive growth of smartphones, QR codes are also being widely used in mobile marketing and advertising campaigns as a fast and effective way of connecting with customers and providing end-user content, including Web links, mobile coupons, airline boarding passes, and other applications such as product tracking, item identification, time tracking, document management, general marketing, etc.
Also, the invention concerns QR codes which include aesthetically pleasing modifications, where an image is merged into the code mainly for improvement of the QR Code visual impact.
Compared with 1-D codes, 2-D codes can hold a larger amount of data in a smaller space, and compared with other 2-D codes, the QR Code and Datamatrix may potentially hold even more data. In addition, advanced error-correction methods and other unique characteristics to detect the code's presence and its positioning allow the QR Code to be read more reliably and at higher speeds than most other codes.
Like written language, barcodes are visual representations of information. Unlike language, however, which humans can read, barcodes are designed to be read and understood (decoded) by computers, using machine-vision systems consisting of optical laser scanners or cameras, more generally by barcode readers, and barcode-interpreting software. The QR Code and Datamatrix high degree of readability under low-contrast conditions may allow printing, laser etching or dot-pin marking (DPM) of a symbol directly onto a part or product.
The QR Code is a 2-D matrix code that conveys information by the arrangement of its dark and light elementary cells, also called “modules,” in columns and rows, i.e. in both the horizontal and vertical directions. Each dark or light module of a QR Code symbol—a specific instance of a code—represents a 0 or 1, thus making it machine intelligible.
A QR code is detected by a 2-dimensional digital image sensor and then digitally analysed by a programmed processor. The processor locates the three distinctive squares at the corners of the QR code image, using a smaller square (or multiple squares) near the fourth corner to normalize the image for size, orientation, and angle of viewing. The small dots throughout the QR code are then converted to binary numbers and validated with an error-correcting code.
The information contained in the QR code can be used to trace a product in a distribution channel, or to detect frauds related to product, such as diversion, theft, alteration, or counterfeiting. However, even though 2D barcodes are increasingly used for anti-counterfeiting applications, they have no built-in protection against copying. They can therefore be very easily duplicated and applied to non-legitimate items, i.e. to counterfeits.